Conventional hemostatic clips of the prior art have been fabricated of stainless steel or tantalum, and are generally made from rectangular wires and formed into symmetrical V or U-shapes. Cartridges for such clips are typically comprised of open box-like structures sized to accept the appropriate U or V-shape with a center rail to support the clips in an inverted position. Various means have been provided to hold the clips on the rail until they are loaded into a forceps type applier. Typical of such prior art clips and cartridges are those illustrated in U.S. Pat. Nos. 3,713,533, 4,076,120, and 4,146,130.
Recent work in the field of molded hemostatic clips made from polymer materials; that is, bio-compatible and/or non-metallic materials, has resulted in a particularly useful clip design. The clip has a configuration wherein the legs are connected at their proximal ends by a resilient hinge area and the distal ends include appropriate latch means. The clip is formed in the open position and has means on the outer surface of its legs by which it can be picked up by a forceps-type applier. The forceps type applier may pick up the clip and the clip closed about a vessel by urging the legs of the clip towards one another until the latching means engages.
In certain of the prior art cartridges used with metal clips, the clip was held in the cartridge by placing the clip under stress so that it is lodged or wedged into a compartment. The stress is increased slightly in order to remove the clip from the cartridge. When making clips of the various polymer materials, it is desired that minimal or no stress be placed on the polymer for extended periods of time. This is especially true of the resilient hinge areas of the polymer clips which, if stressed for considerable lengths of time, that is, a year or more, could become brittle and not function as desired.
Hence, it is desired to produce a cartridge which will keep the non-metallic, bio-compatible clips in place without placing undue stress on the clips yet insure that the clips do not move from their initial position in the cartridge. It is desired that the cartridge be such that the clips may be placed in the cartridge and the cartridge sterilized and further handled with the clips remaining in the position in the cartridge where they were placed until easily removed by a simple forceps-type applying instrument. It is also important that on removing the clip from the cartridge no damage be done to the clip. The removal should be a simple and easy step for the nurse or surgeon using an appropriate forceps-type instrument.